fix some typos (flutter#137144)

*Replace this paragraph with a description of what this PR is changing or adding, and why. Consider including before/after screenshots.*

fix some typos

*List which issues are fixed by this PR. You must list at least one issue.*

*If you had to change anything in the [flutter/tests] repo, include a link to the migration guide as per the [breaking change policy].*

Author: cuishuang

examples/api/lib/material/autocomplete/autocomplete.4.dart

@@ -60,7 +60,7 @@ class _AsyncAutocompleteState extends State<_AsyncAutocomplete > {
   // Whether to consider the fake network to be offline.
   bool _networkEnabled = true;
 
-  // A network error was recieved on the most recent query.
+  // A network error was received on the most recent query.
   bool _networkError = false;
 
   // Calls the "remote" API to search with the given query. Returns null when

packages/flutter/lib/src/cupertino/checkbox.dart

@@ -12,7 +12,7 @@ import 'toggleable.dart';
 // bool _throwShotAway = false;
 // late StateSetter setState;
 
-// The relative values needed to transform a color to it's equivilant focus
+// The relative values needed to transform a color to it's equivalent focus
 // outline color.
 const double _kCupertinoFocusColorOpacity = 0.80;
 const double _kCupertinoFocusColorBrightness = 0.69;

packages/flutter/lib/src/cupertino/radio.dart

@@ -18,7 +18,7 @@ const Size _size = Size(18.0, 18.0);
 const double _kOuterRadius = 7.0;
 const double _kInnerRadius = 2.975;
 
-// The relative values needed to transform a color to its equivilant focus
+// The relative values needed to transform a color to its equivalent focus
 // outline color.
 const double _kCupertinoFocusColorOpacity = 0.80;
 const double _kCupertinoFocusColorBrightness = 0.69;

packages/flutter/lib/src/rendering/object.dart

@@ -2051,7 +2051,7 @@ abstract class RenderObject with DiagnosticableTreeMixin implements HitTestTarge
   /// in its [performLayout] implementation.
   ///
   /// This method is used to implement an assert that ensures the render subtree
-  /// actively performing layout can not get accidently mutated. It's only
+  /// actively performing layout can not get accidentally mutated. It's only
   /// implemented in debug mode and always returns null in release mode.
   ///
   /// The default implementation returns [parent] and overriding is rarely

packages/flutter/lib/src/semantics/semantics_event.dart

@@ -161,7 +161,7 @@ class TapSemanticEvent extends SemanticsEvent {
 /// Using this API is generally not recommended, as it may break a users' expectation of
 /// how a11y focus works and therefore should be just very carefully.
 ///
-/// One possibile use case:
+/// One possible use case:
 /// For example, the currently focused rendering object is replaced by another rendering
 /// object. In general, such design should be avoided if possible. If not, one may want
 /// to refocus the newly added rendering object.